mwifiex: fix race when queuing commands
Running the following script repeatedly on XO-4 with SD8787
produces command timeout and system lockup.
insmod mwifiex_sdio.ko
sleep 1
ifconfig eth0 up
iwlist eth0 scan &
sleep 0.5
rmmod mwifiex_sdio
mwifiex_send_cmd_async() is called for sync as well as async
commands. (mwifiex_send_cmd_sync() internally calls it for
sync command.)
"adapter->cmd_queued" gets filled inside mwifiex_send_cmd_async()
routine for both types of commands. But it is used only for sync
commands in mwifiex_wait_queue_complete(). This could lead to a
race when two threads try to queue a sync command with another
sync/async command simultaneously.
Get rid of global variable and pass command node as a parameter
to mwifiex_wait_queue_complete() to fix the problem.
Cc: <stable@vger.kernel.org> # 3.8
Reported-by: Daniel Drake <dsd@laptop.org>
Tested-by: Daniel Drake <dsd@laptop.org>
Tested-by: Marco Cesarano <marco@marvell.com>
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/mwifiex/main.h b/drivers/net/wireless/mwifiex/main.h
index 553adfb..7035ade 100644
--- a/drivers/net/wireless/mwifiex/main.h
+++ b/drivers/net/wireless/mwifiex/main.h
@@ -723,7 +723,6 @@
u16 cmd_wait_q_required;
struct mwifiex_wait_queue cmd_wait_q;
u8 scan_wait_q_woken;
- struct cmd_ctrl_node *cmd_queued;
spinlock_t queue_lock; /* lock for tx queues */
struct completion fw_load;
u8 country_code[IEEE80211_COUNTRY_STRING_LEN];
@@ -1018,7 +1017,8 @@
struct mwifiex_multicast_list *mcast_list);
int mwifiex_copy_mcast_addr(struct mwifiex_multicast_list *mlist,
struct net_device *dev);
-int mwifiex_wait_queue_complete(struct mwifiex_adapter *adapter);
+int mwifiex_wait_queue_complete(struct mwifiex_adapter *adapter,
+ struct cmd_ctrl_node *cmd_queued);
int mwifiex_bss_start(struct mwifiex_private *priv, struct cfg80211_bss *bss,
struct cfg80211_ssid *req_ssid);
int mwifiex_cancel_hs(struct mwifiex_private *priv, int cmd_type);